Stop Motion Animator and Monkeyjam are two of the most popular. As for a webcam, a quickam pro 9000 is about the best one you are going to find. It’s been recently lowered from $100 to $69.99 on Amazon.com.

Linux is NOT a windows program, it is an Operating System.
Just as Windows XP, Vista, Mac OS X 10.5 is.

Most Linux are Free, 0$.
And involve burning a .iso file to a cd or dvd.
And then rebooting the computer with the cd or dvd in.
Then running the installer or just use the live cd/dvd to see if it fits your needs/all hardware works properly/….